As he and his wife left the foyer, the witness said, Mr Ashby was laughing loudly, “baiting him”, and followed him videoing with his phone.

At one point, he came close to pushing the camera phone close to Mrs Burston and the senator turned on him again.

“So Burston was walking away and Ashby was baiting him and got, I thought, very close to his wife,” said the witness, one of only a handful of people then in the area.

Senator Brian Burston and One Nation adviser James Ashby have a dust-up in the halls of parliament.Source:Supplied

Seen broadly, it confirms One Nation’s innate instability, which already has seen four people meant to be its senators either moving on or being moved on.

They include Malcolm Roberts and Rodney Culleton, who were not even qualified to stand for parliament; Fraser Anning, who refused to stand aside for Mr Roberts; and Senator Burston, who had a tax policy row with Senator Hanson.

In significant part, this instability has come about because One Nation stands for little apart from the cult of Pauline, and its internal dynamics depend on who is in her favour and who isn’t.

Cross her and her troops will mobilise to punish you whenever possible.

And on spectacular occasions, the matter of sex has arisen.

Sexual harassment, no matter by whom, cannot be tolerated and cases should be investigated after a complaint.

But there was no suggestion of harassment when Pauline Hanson began her political career.

The story of how her adviser, David Oldfield, defended Ms Hanson in a Canberra bar just over 20 years ago is one of the more famous political stories.

This initial engagement was followed rather swiftly by encounters of greater intimacy, according to Mr Oldfield, who, incidentally, was in the Rooty Hill RSL when Senator Hanson allegedly groped Senator Burston.

It could be the sex talk is elevated because Senator Hanson is the party leader. Were she a man, there would not be the same interest.

But it could also be the lack of professionalism blighting the party and the low-grade dynamics at its heart.